libxml2 could be made to cause a denial of service by consuming excessive
CPU resources.

Software Description:
- libxml2: GNOME XML library

Details:

Juraj Somorovsky discovered that libxml2 was vulnerable to hash table
collisions. If a user or application linked against libxml2 were tricked
into opening a specially crafted XML file, an attacker could cause a
denial of service.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 11.10:
libxml2 2.7.8.dfsg-4ubuntu0.2

Ubuntu 11.04:
libxml2 2.7.8.dfsg-2ubuntu0.3

Ubuntu 10.10:
libxml2 2.7.7.dfsg-4ubuntu0.4

Ubuntu 10.04 LTS:
libxml2 2.7.6.dfsg-1ubuntu1.4

Ubuntu 8.04 LTS:
libxml2 2.6.31.dfsg-2ubuntu1.8

After a standard system update you need to reboot your computer to make
all the necessary changes.